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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California
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Elizabeth McClintock

In CA perennial herb, terrestrial or aquatic, from short, generally erect caudex, often monoecious; elsewhere shrub, vine, or growing on other plant
Stems sometimes above ground in addition to caudex
Leaves simple or compound, basal (or cauline and 2-ranked)
Inflorescence: generally spike, fleshy, generally ill-smelling; flowers generally many, bisexual or pistillate below, staminate above; bract subtending spike 1, generally showy (petal-like), generally > spike, sometimes sheathing
Flower: perianth parts 4 or 6, free or fused; stamens generally 0, 4, or 6, free or fused; ovary superior to half-inferior and sunken in inflorescence axis, chambers 1–3, stigma ± sessile
Fruit: berry
Seeds 1–many
Genera in family: ± 110 genera, 1800 species: generally tropical, subtropical. Some cultivated for food (Colocasia , taro) or ornamental (Philodendron, Anthurium )
Reference: [Wilson 1960 J Arnold Arbor 41:47–63]
Needle-like crystals in most tissues cause intense irritation when chewed; those of Dieffenbachia, dumb-cane, may induce temporary speechlessness.


Perennial, terrestrial or near edge of water
Leaves 2-ranked; blade folded along midrib, linear to sword-shaped, sheathing, sessile
Inflorescence erect to curved; peduncle leaf-like, fused to bract; bract erect, leaf-like, narrow, green, sessile
Flower bisexual; perianth parts 6, greenish; stamens 6; ovary superior, chambers 2–3
Species in genus: 2–6 species: generally n temp
Etymology: (Latin: aromatic plant)
Reference: [Grayum 1987 Taxon 36:723–729]
Sometimes placed in Acoraceae, because needle-like crystals 0, leaf terminal, leaves and inflorescence bract sessile.


A. calamus L.


Leaf 2–7.5 dm, 7–20 mm wide
Inflorescence 5–10 cm, ± 2 cm wide; peduncle ± = leaves; bract > peduncle, green
Flower greenish yellow
Ecology: Uncommon. Moist ground
Elevation: < 100 m.
Bioregional distribution: n North Coast (Humboldt Co.), Inner North Coast Ranges (Lake Co.), expected elsewhere
Distribution outside California: native to e N.America, Eurasia
Sometimes cultivated for fragrant oil in rhizomes, used medicinally.

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bioregional map for ACORUS%20calamus being generated
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Retrieve Jepson Interchange Index to Plant Names entry for Acorus calamus
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